I think in M2TW already should have been that when you hate faction enough (i think there are 3 levels from dislike to loathe) you get -1 command but morale bonus, and funny battle speeches of course.
I hope there will be some sort of like/dislike gunpowder, but not that every general has them. Also drinking, gambling and other bad traits need to be made less annoying, or at least make them harder to gain.